Periodicity of Nuclear Structure and Emergent Electronic Periodicity

Version 9, 21 September 2026: Manuscript: section 3.6 added (period 6: split into periods 6A, 6B and 6C; the 6A crown in three sub-periods up to ¹⁶⁶Er; lanthanide valences and the open experimental question [refs. Zhang 2016, Boggiano 2025]; period 6B and its second-order inter-axes modelled in polar coordinates up to ²⁰²Hg; period 6C up to ²⁰⁸Pb). Atlas: complete rewriting of periods 6A, 6B and 6C (¹³²Xe, ¹⁶⁶Er and ²⁰²Hg bases), notational hierarchy of positions (axes, inter-axes, inter-inter-axes), redrawn plates; 298 plates. All notations verified to the exact nucleon.